Setting assembler recipes should retain valid ingredients

[spacedog]

I thought I'd be clever and set up a single assembler to switch between making pipes and iron gears, to direct insert into a couple of engine assemblers. I mean, both recipes only take iron plates, so this should have been a piece of cake, right? Right??

Yeah, like 30 minutes and half a dozen combinators later, I basically gave up and precision-clocked the entire circuit so it would work correctly. And then I kind of felt like the whole thing was dumb to do in the first place.

It's fine that switching recipes shoves all the buffered inputs into the output slots, but if the new recipe can make use of any of those ingredients IMO they should just be left in the input slots. I know, the number of recipes with this kind of overlap is probably small, but still... that has to be an easy change.

[Koub]

For completeness, a loosely related suggestion here : viewtopic.php?f=6&t=118708 (about how changing a recipe on an assembler via circuitry should be handled from an ingredient standpoint).

[JOndra91]

TL;DR

Using circuit "set recipe" should not trash resources that are used by new recipe.

Why?

Pumpjack, Chemical plant and Oil refinery have quite similar resource demands. The common ones are Steel plate, Iron gear wheel, Electronic circuit and Pipe.
These are used in different amounts by all the recipes. Oil refinery additionally requires a Stone brick.

So this seemed like a nice opportunity to save some space and have fun with circuits, since these are not generally needed in huge amounts. So with 3 arithmetic combinators and selector combinator I made a circuit to switch between these three recipes, based on which ever items is the least and less than certain amount.

I expected only bricks to be unloaded when switching from Oil refinery, which could be easily handled by a single bot, but instead every ingredient has to unloaded, only to be loaded up again.

[spacedog]

See viewtopic.php?f=6&t=120527, viewtopic.php?f=6&t=118708, and the associated bug reports linked from the second one.

I don't think I've seen a single person disagree with this though. It used to work this way, then got changed to fix a design bug. But the resulting change was a pretty blunt fix for the bug, and IMO caused a usability regression for this feature.

I think the devs need to decide how much friction they want players to encounter when using this feature. It used to be something you could get running with a single combinator, and no extra belts/inserters/chests. Now it's a lot more complicated, both in terms of the required circuitry and the supporting infrastructure. I feel like it will see a lot less use as a result, which is a shame, because it was a nice addition to the game.

[Koub]

[Koub] Merged into an older thread with the same suggestion.

[swecker]

The other post discusses reusing trash slot items, but in case that's not feasible; I think it's important to have this topic around, because not moving ingredients to the trash slot in the first place would solve a lot.
I don't mind having to deal with extraneous ingredients when switching recipes, but having to reset everything when switching between identical recipes makes it more cumbersome than it would ever be worth.